1. Field of the Invention
The present invention relates to laundry additive dispensers, and in particular to such dispensers employing siphoning action in combination with solenoid operated valves to selectively dispense a number of additives to a laundry appliance.
2. Description of the Prior Art
Effective clothes treatment in domestic laundry appliances frequently requires the addition of additives other than a cleaning agent to the clothes treatment solution. Additives such as fabric softener, water softener' bleach and the like may be necessary depending upon local water conditions and the nature of the clothes to be treated. Laundry appliances known in the art generally complete a cycle of operation including a wash or agitation portion, a spin portion to centrifugally extract the wash liquid, a rinse portion, and a final liquid extraction spin portion. A problem in the art has been providing a laundry additive dispenser which automatically dispenses appropriate laundry additives at selected times during a cycle of operation coordinated with the particular portion of the cycle in which the additive can be most effectively utilized. Thus it is normally desirable to dispense the detergent and bleach into a wash portion of the cycle, while on the other hand it is preferable to delay dispensing of a fabric softener until a later portion of the cycle.
Devices for dispensing a single laundry additive at a selected time during a cycle of operation are known in the art, such as those disclosed in U.S. Pat. Nos. 3,057,181, 2,974,516 and 2,887,862. The first and last of these patents utilize a siphon contained in the dispenser to dispense a water-additive solution into a clothes treatment area when a solution level in the dispenser reaches a height so as to begin the siphoning action. U.S. Pat. No. 2,974,516 utilizes a control circuit for energizing solenoids to open and close valves at selected times during a cycle of operation to allow flow of additive into the clothes treatment area at those times.